Add git-replace to .gitignore
[git/jrn.git] / refs.c
blob6a136512c716c2169aed82107d077aad5142095c
1 #include "cache.h"
2 #include "refs.h"
3 #include "object.h"
4 #include "tag.h"
5 #include "dir.h"
7 /* ISSYMREF=01 and ISPACKED=02 are public interfaces */
8 #define REF_KNOWS_PEELED 04
10 struct ref_list {
11 struct ref_list *next;
12 unsigned char flag; /* ISSYMREF? ISPACKED? */
13 unsigned char sha1[20];
14 unsigned char peeled[20];
15 char name[FLEX_ARRAY];
18 static const char *parse_ref_line(char *line, unsigned char *sha1)
21 * 42: the answer to everything.
23 * In this case, it happens to be the answer to
24 * 40 (length of sha1 hex representation)
25 * +1 (space in between hex and name)
26 * +1 (newline at the end of the line)
28 int len = strlen(line) - 42;
30 if (len <= 0)
31 return NULL;
32 if (get_sha1_hex(line, sha1) < 0)
33 return NULL;
34 if (!isspace(line[40]))
35 return NULL;
36 line += 41;
37 if (isspace(*line))
38 return NULL;
39 if (line[len] != '\n')
40 return NULL;
41 line[len] = 0;
43 return line;
46 static struct ref_list *add_ref(const char *name, const unsigned char *sha1,
47 int flag, struct ref_list *list,
48 struct ref_list **new_entry)
50 int len;
51 struct ref_list *entry;
53 /* Allocate it and add it in.. */
54 len = strlen(name) + 1;
55 entry = xmalloc(sizeof(struct ref_list) + len);
56 hashcpy(entry->sha1, sha1);
57 hashclr(entry->peeled);
58 memcpy(entry->name, name, len);
59 entry->flag = flag;
60 entry->next = list;
61 if (new_entry)
62 *new_entry = entry;
63 return entry;
66 /* merge sort the ref list */
67 static struct ref_list *sort_ref_list(struct ref_list *list)
69 int psize, qsize, last_merge_count, cmp;
70 struct ref_list *p, *q, *l, *e;
71 struct ref_list *new_list = list;
72 int k = 1;
73 int merge_count = 0;
75 if (!list)
76 return list;
78 do {
79 last_merge_count = merge_count;
80 merge_count = 0;
82 psize = 0;
84 p = new_list;
85 q = new_list;
86 new_list = NULL;
87 l = NULL;
89 while (p) {
90 merge_count++;
92 while (psize < k && q->next) {
93 q = q->next;
94 psize++;
96 qsize = k;
98 while ((psize > 0) || (qsize > 0 && q)) {
99 if (qsize == 0 || !q) {
100 e = p;
101 p = p->next;
102 psize--;
103 } else if (psize == 0) {
104 e = q;
105 q = q->next;
106 qsize--;
107 } else {
108 cmp = strcmp(q->name, p->name);
109 if (cmp < 0) {
110 e = q;
111 q = q->next;
112 qsize--;
113 } else if (cmp > 0) {
114 e = p;
115 p = p->next;
116 psize--;
117 } else {
118 if (hashcmp(q->sha1, p->sha1))
119 die("Duplicated ref, and SHA1s don't match: %s",
120 q->name);
121 warning("Duplicated ref: %s", q->name);
122 e = q;
123 q = q->next;
124 qsize--;
125 free(e);
126 e = p;
127 p = p->next;
128 psize--;
132 e->next = NULL;
134 if (l)
135 l->next = e;
136 if (!new_list)
137 new_list = e;
138 l = e;
141 p = q;
144 k = k * 2;
145 } while ((last_merge_count != merge_count) || (last_merge_count != 1));
147 return new_list;
151 * Future: need to be in "struct repository"
152 * when doing a full libification.
154 static struct cached_refs {
155 char did_loose;
156 char did_packed;
157 struct ref_list *loose;
158 struct ref_list *packed;
159 } cached_refs;
160 static struct ref_list *current_ref;
162 static struct ref_list *extra_refs;
164 static void free_ref_list(struct ref_list *list)
166 struct ref_list *next;
167 for ( ; list; list = next) {
168 next = list->next;
169 free(list);
173 static void invalidate_cached_refs(void)
175 struct cached_refs *ca = &cached_refs;
177 if (ca->did_loose && ca->loose)
178 free_ref_list(ca->loose);
179 if (ca->did_packed && ca->packed)
180 free_ref_list(ca->packed);
181 ca->loose = ca->packed = NULL;
182 ca->did_loose = ca->did_packed = 0;
185 static void read_packed_refs(FILE *f, struct cached_refs *cached_refs)
187 struct ref_list *list = NULL;
188 struct ref_list *last = NULL;
189 char refline[PATH_MAX];
190 int flag = REF_ISPACKED;
192 while (fgets(refline, sizeof(refline), f)) {
193 unsigned char sha1[20];
194 const char *name;
195 static const char header[] = "# pack-refs with:";
197 if (!strncmp(refline, header, sizeof(header)-1)) {
198 const char *traits = refline + sizeof(header) - 1;
199 if (strstr(traits, " peeled "))
200 flag |= REF_KNOWS_PEELED;
201 /* perhaps other traits later as well */
202 continue;
205 name = parse_ref_line(refline, sha1);
206 if (name) {
207 list = add_ref(name, sha1, flag, list, &last);
208 continue;
210 if (last &&
211 refline[0] == '^' &&
212 strlen(refline) == 42 &&
213 refline[41] == '\n' &&
214 !get_sha1_hex(refline + 1, sha1))
215 hashcpy(last->peeled, sha1);
217 cached_refs->packed = sort_ref_list(list);
220 void add_extra_ref(const char *name, const unsigned char *sha1, int flag)
222 extra_refs = add_ref(name, sha1, flag, extra_refs, NULL);
225 void clear_extra_refs(void)
227 free_ref_list(extra_refs);
228 extra_refs = NULL;
231 static struct ref_list *get_packed_refs(void)
233 if (!cached_refs.did_packed) {
234 FILE *f = fopen(git_path("packed-refs"), "r");
235 cached_refs.packed = NULL;
236 if (f) {
237 read_packed_refs(f, &cached_refs);
238 fclose(f);
240 cached_refs.did_packed = 1;
242 return cached_refs.packed;
245 static struct ref_list *get_ref_dir(const char *base, struct ref_list *list)
247 DIR *dir = opendir(git_path("%s", base));
249 if (dir) {
250 struct dirent *de;
251 int baselen = strlen(base);
252 char *ref = xmalloc(baselen + 257);
254 memcpy(ref, base, baselen);
255 if (baselen && base[baselen-1] != '/')
256 ref[baselen++] = '/';
258 while ((de = readdir(dir)) != NULL) {
259 unsigned char sha1[20];
260 struct stat st;
261 int flag;
262 int namelen;
264 if (de->d_name[0] == '.')
265 continue;
266 namelen = strlen(de->d_name);
267 if (namelen > 255)
268 continue;
269 if (has_extension(de->d_name, ".lock"))
270 continue;
271 memcpy(ref + baselen, de->d_name, namelen+1);
272 if (stat(git_path("%s", ref), &st) < 0)
273 continue;
274 if (S_ISDIR(st.st_mode)) {
275 list = get_ref_dir(ref, list);
276 continue;
278 if (!resolve_ref(ref, sha1, 1, &flag))
279 hashclr(sha1);
280 list = add_ref(ref, sha1, flag, list, NULL);
282 free(ref);
283 closedir(dir);
285 return sort_ref_list(list);
288 struct warn_if_dangling_data {
289 const char *refname;
290 const char *msg_fmt;
293 static int warn_if_dangling_symref(const char *refname, const unsigned char *sha1,
294 int flags, void *cb_data)
296 struct warn_if_dangling_data *d = cb_data;
297 const char *resolves_to;
298 unsigned char junk[20];
300 if (!(flags & REF_ISSYMREF))
301 return 0;
303 resolves_to = resolve_ref(refname, junk, 0, NULL);
304 if (!resolves_to || strcmp(resolves_to, d->refname))
305 return 0;
307 printf(d->msg_fmt, refname);
308 return 0;
311 void warn_dangling_symref(const char *msg_fmt, const char *refname)
313 struct warn_if_dangling_data data = { refname, msg_fmt };
314 for_each_rawref(warn_if_dangling_symref, &data);
317 static struct ref_list *get_loose_refs(void)
319 if (!cached_refs.did_loose) {
320 cached_refs.loose = get_ref_dir("refs", NULL);
321 cached_refs.did_loose = 1;
323 return cached_refs.loose;
326 /* We allow "recursive" symbolic refs. Only within reason, though */
327 #define MAXDEPTH 5
328 #define MAXREFLEN (1024)
330 static int resolve_gitlink_packed_ref(char *name, int pathlen, const char *refname, unsigned char *result)
332 FILE *f;
333 struct cached_refs refs;
334 struct ref_list *ref;
335 int retval;
337 strcpy(name + pathlen, "packed-refs");
338 f = fopen(name, "r");
339 if (!f)
340 return -1;
341 read_packed_refs(f, &refs);
342 fclose(f);
343 ref = refs.packed;
344 retval = -1;
345 while (ref) {
346 if (!strcmp(ref->name, refname)) {
347 retval = 0;
348 memcpy(result, ref->sha1, 20);
349 break;
351 ref = ref->next;
353 free_ref_list(refs.packed);
354 return retval;
357 static int resolve_gitlink_ref_recursive(char *name, int pathlen, const char *refname, unsigned char *result, int recursion)
359 int fd, len = strlen(refname);
360 char buffer[128], *p;
362 if (recursion > MAXDEPTH || len > MAXREFLEN)
363 return -1;
364 memcpy(name + pathlen, refname, len+1);
365 fd = open(name, O_RDONLY);
366 if (fd < 0)
367 return resolve_gitlink_packed_ref(name, pathlen, refname, result);
369 len = read(fd, buffer, sizeof(buffer)-1);
370 close(fd);
371 if (len < 0)
372 return -1;
373 while (len && isspace(buffer[len-1]))
374 len--;
375 buffer[len] = 0;
377 /* Was it a detached head or an old-fashioned symlink? */
378 if (!get_sha1_hex(buffer, result))
379 return 0;
381 /* Symref? */
382 if (strncmp(buffer, "ref:", 4))
383 return -1;
384 p = buffer + 4;
385 while (isspace(*p))
386 p++;
388 return resolve_gitlink_ref_recursive(name, pathlen, p, result, recursion+1);
391 int resolve_gitlink_ref(const char *path, const char *refname, unsigned char *result)
393 int len = strlen(path), retval;
394 char *gitdir;
395 const char *tmp;
397 while (len && path[len-1] == '/')
398 len--;
399 if (!len)
400 return -1;
401 gitdir = xmalloc(len + MAXREFLEN + 8);
402 memcpy(gitdir, path, len);
403 memcpy(gitdir + len, "/.git", 6);
404 len += 5;
406 tmp = read_gitfile_gently(gitdir);
407 if (tmp) {
408 free(gitdir);
409 len = strlen(tmp);
410 gitdir = xmalloc(len + MAXREFLEN + 3);
411 memcpy(gitdir, tmp, len);
413 gitdir[len] = '/';
414 gitdir[++len] = '\0';
415 retval = resolve_gitlink_ref_recursive(gitdir, len, refname, result, 0);
416 free(gitdir);
417 return retval;
421 * If the "reading" argument is set, this function finds out what _object_
422 * the ref points at by "reading" the ref. The ref, if it is not symbolic,
423 * has to exist, and if it is symbolic, it has to point at an existing ref,
424 * because the "read" goes through the symref to the ref it points at.
426 * The access that is not "reading" may often be "writing", but does not
427 * have to; it can be merely checking _where it leads to_. If it is a
428 * prelude to "writing" to the ref, a write to a symref that points at
429 * yet-to-be-born ref will create the real ref pointed by the symref.
430 * reading=0 allows the caller to check where such a symref leads to.
432 const char *resolve_ref(const char *ref, unsigned char *sha1, int reading, int *flag)
434 int depth = MAXDEPTH;
435 ssize_t len;
436 char buffer[256];
437 static char ref_buffer[256];
439 if (flag)
440 *flag = 0;
442 for (;;) {
443 char path[PATH_MAX];
444 struct stat st;
445 char *buf;
446 int fd;
448 if (--depth < 0)
449 return NULL;
451 git_snpath(path, sizeof(path), "%s", ref);
452 /* Special case: non-existing file. */
453 if (lstat(path, &st) < 0) {
454 struct ref_list *list = get_packed_refs();
455 while (list) {
456 if (!strcmp(ref, list->name)) {
457 hashcpy(sha1, list->sha1);
458 if (flag)
459 *flag |= REF_ISPACKED;
460 return ref;
462 list = list->next;
464 if (reading || errno != ENOENT)
465 return NULL;
466 hashclr(sha1);
467 return ref;
470 /* Follow "normalized" - ie "refs/.." symlinks by hand */
471 if (S_ISLNK(st.st_mode)) {
472 len = readlink(path, buffer, sizeof(buffer)-1);
473 if (len >= 5 && !memcmp("refs/", buffer, 5)) {
474 buffer[len] = 0;
475 strcpy(ref_buffer, buffer);
476 ref = ref_buffer;
477 if (flag)
478 *flag |= REF_ISSYMREF;
479 continue;
483 /* Is it a directory? */
484 if (S_ISDIR(st.st_mode)) {
485 errno = EISDIR;
486 return NULL;
490 * Anything else, just open it and try to use it as
491 * a ref
493 fd = open(path, O_RDONLY);
494 if (fd < 0)
495 return NULL;
496 len = read_in_full(fd, buffer, sizeof(buffer)-1);
497 close(fd);
500 * Is it a symbolic ref?
502 if (len < 4 || memcmp("ref:", buffer, 4))
503 break;
504 buf = buffer + 4;
505 len -= 4;
506 while (len && isspace(*buf))
507 buf++, len--;
508 while (len && isspace(buf[len-1]))
509 len--;
510 buf[len] = 0;
511 memcpy(ref_buffer, buf, len + 1);
512 ref = ref_buffer;
513 if (flag)
514 *flag |= REF_ISSYMREF;
516 if (len < 40 || get_sha1_hex(buffer, sha1))
517 return NULL;
518 return ref;
521 int read_ref(const char *ref, unsigned char *sha1)
523 if (resolve_ref(ref, sha1, 1, NULL))
524 return 0;
525 return -1;
528 #define DO_FOR_EACH_INCLUDE_BROKEN 01
529 static int do_one_ref(const char *base, each_ref_fn fn, int trim,
530 int flags, void *cb_data, struct ref_list *entry)
532 if (strncmp(base, entry->name, trim))
533 return 0;
534 if (!(flags & DO_FOR_EACH_INCLUDE_BROKEN)) {
535 if (is_null_sha1(entry->sha1))
536 return 0;
537 if (!has_sha1_file(entry->sha1)) {
538 error("%s does not point to a valid object!", entry->name);
539 return 0;
542 current_ref = entry;
543 return fn(entry->name + trim, entry->sha1, entry->flag, cb_data);
546 int peel_ref(const char *ref, unsigned char *sha1)
548 int flag;
549 unsigned char base[20];
550 struct object *o;
552 if (current_ref && (current_ref->name == ref
553 || !strcmp(current_ref->name, ref))) {
554 if (current_ref->flag & REF_KNOWS_PEELED) {
555 hashcpy(sha1, current_ref->peeled);
556 return 0;
558 hashcpy(base, current_ref->sha1);
559 goto fallback;
562 if (!resolve_ref(ref, base, 1, &flag))
563 return -1;
565 if ((flag & REF_ISPACKED)) {
566 struct ref_list *list = get_packed_refs();
568 while (list) {
569 if (!strcmp(list->name, ref)) {
570 if (list->flag & REF_KNOWS_PEELED) {
571 hashcpy(sha1, list->peeled);
572 return 0;
574 /* older pack-refs did not leave peeled ones */
575 break;
577 list = list->next;
581 fallback:
582 o = parse_object(base);
583 if (o && o->type == OBJ_TAG) {
584 o = deref_tag(o, ref, 0);
585 if (o) {
586 hashcpy(sha1, o->sha1);
587 return 0;
590 return -1;
593 static int do_for_each_ref(const char *base, each_ref_fn fn, int trim,
594 int flags, void *cb_data)
596 int retval = 0;
597 struct ref_list *packed = get_packed_refs();
598 struct ref_list *loose = get_loose_refs();
600 struct ref_list *extra;
602 for (extra = extra_refs; extra; extra = extra->next)
603 retval = do_one_ref(base, fn, trim, flags, cb_data, extra);
605 while (packed && loose) {
606 struct ref_list *entry;
607 int cmp = strcmp(packed->name, loose->name);
608 if (!cmp) {
609 packed = packed->next;
610 continue;
612 if (cmp > 0) {
613 entry = loose;
614 loose = loose->next;
615 } else {
616 entry = packed;
617 packed = packed->next;
619 retval = do_one_ref(base, fn, trim, flags, cb_data, entry);
620 if (retval)
621 goto end_each;
624 for (packed = packed ? packed : loose; packed; packed = packed->next) {
625 retval = do_one_ref(base, fn, trim, flags, cb_data, packed);
626 if (retval)
627 goto end_each;
630 end_each:
631 current_ref = NULL;
632 return retval;
635 int head_ref(each_ref_fn fn, void *cb_data)
637 unsigned char sha1[20];
638 int flag;
640 if (resolve_ref("HEAD", sha1, 1, &flag))
641 return fn("HEAD", sha1, flag, cb_data);
642 return 0;
645 int for_each_ref(each_ref_fn fn, void *cb_data)
647 return do_for_each_ref("refs/", fn, 0, 0, cb_data);
650 int for_each_ref_in(const char *prefix, each_ref_fn fn, void *cb_data)
652 return do_for_each_ref(prefix, fn, strlen(prefix), 0, cb_data);
655 int for_each_tag_ref(each_ref_fn fn, void *cb_data)
657 return for_each_ref_in("refs/tags/", fn, cb_data);
660 int for_each_branch_ref(each_ref_fn fn, void *cb_data)
662 return for_each_ref_in("refs/heads/", fn, cb_data);
665 int for_each_remote_ref(each_ref_fn fn, void *cb_data)
667 return for_each_ref_in("refs/remotes/", fn, cb_data);
670 int for_each_replace_ref(each_ref_fn fn, void *cb_data)
672 return do_for_each_ref("refs/replace/", fn, 13, 0, cb_data);
675 int for_each_rawref(each_ref_fn fn, void *cb_data)
677 return do_for_each_ref("refs/", fn, 0,
678 DO_FOR_EACH_INCLUDE_BROKEN, cb_data);
682 * Make sure "ref" is something reasonable to have under ".git/refs/";
683 * We do not like it if:
685 * - any path component of it begins with ".", or
686 * - it has double dots "..", or
687 * - it has ASCII control character, "~", "^", ":" or SP, anywhere, or
688 * - it ends with a "/".
689 * - it ends with ".lock"
690 * - it contains a "\" (backslash)
693 static inline int bad_ref_char(int ch)
695 if (((unsigned) ch) <= ' ' ||
696 ch == '~' || ch == '^' || ch == ':' || ch == '\\')
697 return 1;
698 /* 2.13 Pattern Matching Notation */
699 if (ch == '?' || ch == '[') /* Unsupported */
700 return 1;
701 if (ch == '*') /* Supported at the end */
702 return 2;
703 return 0;
706 int check_ref_format(const char *ref)
708 int ch, level, bad_type, last;
709 int ret = CHECK_REF_FORMAT_OK;
710 const char *cp = ref;
712 level = 0;
713 while (1) {
714 while ((ch = *cp++) == '/')
715 ; /* tolerate duplicated slashes */
716 if (!ch)
717 /* should not end with slashes */
718 return CHECK_REF_FORMAT_ERROR;
720 /* we are at the beginning of the path component */
721 if (ch == '.')
722 return CHECK_REF_FORMAT_ERROR;
723 bad_type = bad_ref_char(ch);
724 if (bad_type) {
725 if (bad_type == 2 && (!*cp || *cp == '/') &&
726 ret == CHECK_REF_FORMAT_OK)
727 ret = CHECK_REF_FORMAT_WILDCARD;
728 else
729 return CHECK_REF_FORMAT_ERROR;
732 last = ch;
733 /* scan the rest of the path component */
734 while ((ch = *cp++) != 0) {
735 bad_type = bad_ref_char(ch);
736 if (bad_type)
737 return CHECK_REF_FORMAT_ERROR;
738 if (ch == '/')
739 break;
740 if (last == '.' && ch == '.')
741 return CHECK_REF_FORMAT_ERROR;
742 if (last == '@' && ch == '{')
743 return CHECK_REF_FORMAT_ERROR;
744 last = ch;
746 level++;
747 if (!ch) {
748 if (ref <= cp - 2 && cp[-2] == '.')
749 return CHECK_REF_FORMAT_ERROR;
750 if (level < 2)
751 return CHECK_REF_FORMAT_ONELEVEL;
752 if (has_extension(ref, ".lock"))
753 return CHECK_REF_FORMAT_ERROR;
754 return ret;
759 const char *prettify_refname(const char *name)
761 return name + (
762 !prefixcmp(name, "refs/heads/") ? 11 :
763 !prefixcmp(name, "refs/tags/") ? 10 :
764 !prefixcmp(name, "refs/remotes/") ? 13 :
768 const char *ref_rev_parse_rules[] = {
769 "%.*s",
770 "refs/%.*s",
771 "refs/tags/%.*s",
772 "refs/heads/%.*s",
773 "refs/remotes/%.*s",
774 "refs/remotes/%.*s/HEAD",
775 NULL
778 const char *ref_fetch_rules[] = {
779 "%.*s",
780 "refs/%.*s",
781 "refs/heads/%.*s",
782 NULL
785 int refname_match(const char *abbrev_name, const char *full_name, const char **rules)
787 const char **p;
788 const int abbrev_name_len = strlen(abbrev_name);
790 for (p = rules; *p; p++) {
791 if (!strcmp(full_name, mkpath(*p, abbrev_name_len, abbrev_name))) {
792 return 1;
796 return 0;
799 static struct ref_lock *verify_lock(struct ref_lock *lock,
800 const unsigned char *old_sha1, int mustexist)
802 if (!resolve_ref(lock->ref_name, lock->old_sha1, mustexist, NULL)) {
803 error("Can't verify ref %s", lock->ref_name);
804 unlock_ref(lock);
805 return NULL;
807 if (hashcmp(lock->old_sha1, old_sha1)) {
808 error("Ref %s is at %s but expected %s", lock->ref_name,
809 sha1_to_hex(lock->old_sha1), sha1_to_hex(old_sha1));
810 unlock_ref(lock);
811 return NULL;
813 return lock;
816 static int remove_empty_directories(const char *file)
818 /* we want to create a file but there is a directory there;
819 * if that is an empty directory (or a directory that contains
820 * only empty directories), remove them.
822 struct strbuf path;
823 int result;
825 strbuf_init(&path, 20);
826 strbuf_addstr(&path, file);
828 result = remove_dir_recursively(&path, 1);
830 strbuf_release(&path);
832 return result;
835 static int is_refname_available(const char *ref, const char *oldref,
836 struct ref_list *list, int quiet)
838 int namlen = strlen(ref); /* e.g. 'foo/bar' */
839 while (list) {
840 /* list->name could be 'foo' or 'foo/bar/baz' */
841 if (!oldref || strcmp(oldref, list->name)) {
842 int len = strlen(list->name);
843 int cmplen = (namlen < len) ? namlen : len;
844 const char *lead = (namlen < len) ? list->name : ref;
845 if (!strncmp(ref, list->name, cmplen) &&
846 lead[cmplen] == '/') {
847 if (!quiet)
848 error("'%s' exists; cannot create '%s'",
849 list->name, ref);
850 return 0;
853 list = list->next;
855 return 1;
858 static struct ref_lock *lock_ref_sha1_basic(const char *ref, const unsigned char *old_sha1, int flags, int *type_p)
860 char *ref_file;
861 const char *orig_ref = ref;
862 struct ref_lock *lock;
863 int last_errno = 0;
864 int type, lflags;
865 int mustexist = (old_sha1 && !is_null_sha1(old_sha1));
866 int missing = 0;
868 lock = xcalloc(1, sizeof(struct ref_lock));
869 lock->lock_fd = -1;
871 ref = resolve_ref(ref, lock->old_sha1, mustexist, &type);
872 if (!ref && errno == EISDIR) {
873 /* we are trying to lock foo but we used to
874 * have foo/bar which now does not exist;
875 * it is normal for the empty directory 'foo'
876 * to remain.
878 ref_file = git_path("%s", orig_ref);
879 if (remove_empty_directories(ref_file)) {
880 last_errno = errno;
881 error("there are still refs under '%s'", orig_ref);
882 goto error_return;
884 ref = resolve_ref(orig_ref, lock->old_sha1, mustexist, &type);
886 if (type_p)
887 *type_p = type;
888 if (!ref) {
889 last_errno = errno;
890 error("unable to resolve reference %s: %s",
891 orig_ref, strerror(errno));
892 goto error_return;
894 missing = is_null_sha1(lock->old_sha1);
895 /* When the ref did not exist and we are creating it,
896 * make sure there is no existing ref that is packed
897 * whose name begins with our refname, nor a ref whose
898 * name is a proper prefix of our refname.
900 if (missing &&
901 !is_refname_available(ref, NULL, get_packed_refs(), 0)) {
902 last_errno = ENOTDIR;
903 goto error_return;
906 lock->lk = xcalloc(1, sizeof(struct lock_file));
908 lflags = LOCK_DIE_ON_ERROR;
909 if (flags & REF_NODEREF) {
910 ref = orig_ref;
911 lflags |= LOCK_NODEREF;
913 lock->ref_name = xstrdup(ref);
914 lock->orig_ref_name = xstrdup(orig_ref);
915 ref_file = git_path("%s", ref);
916 if (missing)
917 lock->force_write = 1;
918 if ((flags & REF_NODEREF) && (type & REF_ISSYMREF))
919 lock->force_write = 1;
921 if (safe_create_leading_directories(ref_file)) {
922 last_errno = errno;
923 error("unable to create directory for %s", ref_file);
924 goto error_return;
927 lock->lock_fd = hold_lock_file_for_update(lock->lk, ref_file, lflags);
928 return old_sha1 ? verify_lock(lock, old_sha1, mustexist) : lock;
930 error_return:
931 unlock_ref(lock);
932 errno = last_errno;
933 return NULL;
936 struct ref_lock *lock_ref_sha1(const char *ref, const unsigned char *old_sha1)
938 char refpath[PATH_MAX];
939 if (check_ref_format(ref))
940 return NULL;
941 strcpy(refpath, mkpath("refs/%s", ref));
942 return lock_ref_sha1_basic(refpath, old_sha1, 0, NULL);
945 struct ref_lock *lock_any_ref_for_update(const char *ref, const unsigned char *old_sha1, int flags)
947 switch (check_ref_format(ref)) {
948 default:
949 return NULL;
950 case 0:
951 case CHECK_REF_FORMAT_ONELEVEL:
952 return lock_ref_sha1_basic(ref, old_sha1, flags, NULL);
956 static struct lock_file packlock;
958 static int repack_without_ref(const char *refname)
960 struct ref_list *list, *packed_ref_list;
961 int fd;
962 int found = 0;
964 packed_ref_list = get_packed_refs();
965 for (list = packed_ref_list; list; list = list->next) {
966 if (!strcmp(refname, list->name)) {
967 found = 1;
968 break;
971 if (!found)
972 return 0;
973 fd = hold_lock_file_for_update(&packlock, git_path("packed-refs"), 0);
974 if (fd < 0)
975 return error("cannot delete '%s' from packed refs", refname);
977 for (list = packed_ref_list; list; list = list->next) {
978 char line[PATH_MAX + 100];
979 int len;
981 if (!strcmp(refname, list->name))
982 continue;
983 len = snprintf(line, sizeof(line), "%s %s\n",
984 sha1_to_hex(list->sha1), list->name);
985 /* this should not happen but just being defensive */
986 if (len > sizeof(line))
987 die("too long a refname '%s'", list->name);
988 write_or_die(fd, line, len);
990 return commit_lock_file(&packlock);
993 int delete_ref(const char *refname, const unsigned char *sha1, int delopt)
995 struct ref_lock *lock;
996 int err, i = 0, ret = 0, flag = 0;
998 lock = lock_ref_sha1_basic(refname, sha1, 0, &flag);
999 if (!lock)
1000 return 1;
1001 if (!(flag & REF_ISPACKED) || flag & REF_ISSYMREF) {
1002 /* loose */
1003 const char *path;
1005 if (!(delopt & REF_NODEREF)) {
1006 i = strlen(lock->lk->filename) - 5; /* .lock */
1007 lock->lk->filename[i] = 0;
1008 path = lock->lk->filename;
1009 } else {
1010 path = git_path("%s", refname);
1012 err = unlink_or_warn(path);
1013 if (err && errno != ENOENT)
1014 ret = 1;
1016 if (!(delopt & REF_NODEREF))
1017 lock->lk->filename[i] = '.';
1019 /* removing the loose one could have resurrected an earlier
1020 * packed one. Also, if it was not loose we need to repack
1021 * without it.
1023 ret |= repack_without_ref(refname);
1025 unlink_or_warn(git_path("logs/%s", lock->ref_name));
1026 invalidate_cached_refs();
1027 unlock_ref(lock);
1028 return ret;
1031 int rename_ref(const char *oldref, const char *newref, const char *logmsg)
1033 static const char renamed_ref[] = "RENAMED-REF";
1034 unsigned char sha1[20], orig_sha1[20];
1035 int flag = 0, logmoved = 0;
1036 struct ref_lock *lock;
1037 struct stat loginfo;
1038 int log = !lstat(git_path("logs/%s", oldref), &loginfo);
1039 const char *symref = NULL;
1041 if (log && S_ISLNK(loginfo.st_mode))
1042 return error("reflog for %s is a symlink", oldref);
1044 symref = resolve_ref(oldref, orig_sha1, 1, &flag);
1045 if (flag & REF_ISSYMREF)
1046 return error("refname %s is a symbolic ref, renaming it is not supported",
1047 oldref);
1048 if (!symref)
1049 return error("refname %s not found", oldref);
1051 if (!is_refname_available(newref, oldref, get_packed_refs(), 0))
1052 return 1;
1054 if (!is_refname_available(newref, oldref, get_loose_refs(), 0))
1055 return 1;
1057 lock = lock_ref_sha1_basic(renamed_ref, NULL, 0, NULL);
1058 if (!lock)
1059 return error("unable to lock %s", renamed_ref);
1060 lock->force_write = 1;
1061 if (write_ref_sha1(lock, orig_sha1, logmsg))
1062 return error("unable to save current sha1 in %s", renamed_ref);
1064 if (log && rename(git_path("logs/%s", oldref), git_path("tmp-renamed-log")))
1065 return error("unable to move logfile logs/%s to tmp-renamed-log: %s",
1066 oldref, strerror(errno));
1068 if (delete_ref(oldref, orig_sha1, REF_NODEREF)) {
1069 error("unable to delete old %s", oldref);
1070 goto rollback;
1073 if (resolve_ref(newref, sha1, 1, &flag) && delete_ref(newref, sha1, REF_NODEREF)) {
1074 if (errno==EISDIR) {
1075 if (remove_empty_directories(git_path("%s", newref))) {
1076 error("Directory not empty: %s", newref);
1077 goto rollback;
1079 } else {
1080 error("unable to delete existing %s", newref);
1081 goto rollback;
1085 if (log && safe_create_leading_directories(git_path("logs/%s", newref))) {
1086 error("unable to create directory for %s", newref);
1087 goto rollback;
1090 retry:
1091 if (log && rename(git_path("tmp-renamed-log"), git_path("logs/%s", newref))) {
1092 if (errno==EISDIR || errno==ENOTDIR) {
1094 * rename(a, b) when b is an existing
1095 * directory ought to result in ISDIR, but
1096 * Solaris 5.8 gives ENOTDIR. Sheesh.
1098 if (remove_empty_directories(git_path("logs/%s", newref))) {
1099 error("Directory not empty: logs/%s", newref);
1100 goto rollback;
1102 goto retry;
1103 } else {
1104 error("unable to move logfile tmp-renamed-log to logs/%s: %s",
1105 newref, strerror(errno));
1106 goto rollback;
1109 logmoved = log;
1111 lock = lock_ref_sha1_basic(newref, NULL, 0, NULL);
1112 if (!lock) {
1113 error("unable to lock %s for update", newref);
1114 goto rollback;
1116 lock->force_write = 1;
1117 hashcpy(lock->old_sha1, orig_sha1);
1118 if (write_ref_sha1(lock, orig_sha1, logmsg)) {
1119 error("unable to write current sha1 into %s", newref);
1120 goto rollback;
1123 return 0;
1125 rollback:
1126 lock = lock_ref_sha1_basic(oldref, NULL, 0, NULL);
1127 if (!lock) {
1128 error("unable to lock %s for rollback", oldref);
1129 goto rollbacklog;
1132 lock->force_write = 1;
1133 flag = log_all_ref_updates;
1134 log_all_ref_updates = 0;
1135 if (write_ref_sha1(lock, orig_sha1, NULL))
1136 error("unable to write current sha1 into %s", oldref);
1137 log_all_ref_updates = flag;
1139 rollbacklog:
1140 if (logmoved && rename(git_path("logs/%s", newref), git_path("logs/%s", oldref)))
1141 error("unable to restore logfile %s from %s: %s",
1142 oldref, newref, strerror(errno));
1143 if (!logmoved && log &&
1144 rename(git_path("tmp-renamed-log"), git_path("logs/%s", oldref)))
1145 error("unable to restore logfile %s from tmp-renamed-log: %s",
1146 oldref, strerror(errno));
1148 return 1;
1151 int close_ref(struct ref_lock *lock)
1153 if (close_lock_file(lock->lk))
1154 return -1;
1155 lock->lock_fd = -1;
1156 return 0;
1159 int commit_ref(struct ref_lock *lock)
1161 if (commit_lock_file(lock->lk))
1162 return -1;
1163 lock->lock_fd = -1;
1164 return 0;
1167 void unlock_ref(struct ref_lock *lock)
1169 /* Do not free lock->lk -- atexit() still looks at them */
1170 if (lock->lk)
1171 rollback_lock_file(lock->lk);
1172 free(lock->ref_name);
1173 free(lock->orig_ref_name);
1174 free(lock);
1178 * copy the reflog message msg to buf, which has been allocated sufficiently
1179 * large, while cleaning up the whitespaces. Especially, convert LF to space,
1180 * because reflog file is one line per entry.
1182 static int copy_msg(char *buf, const char *msg)
1184 char *cp = buf;
1185 char c;
1186 int wasspace = 1;
1188 *cp++ = '\t';
1189 while ((c = *msg++)) {
1190 if (wasspace && isspace(c))
1191 continue;
1192 wasspace = isspace(c);
1193 if (wasspace)
1194 c = ' ';
1195 *cp++ = c;
1197 while (buf < cp && isspace(cp[-1]))
1198 cp--;
1199 *cp++ = '\n';
1200 return cp - buf;
1203 static int log_ref_write(const char *ref_name, const unsigned char *old_sha1,
1204 const unsigned char *new_sha1, const char *msg)
1206 int logfd, written, oflags = O_APPEND | O_WRONLY;
1207 unsigned maxlen, len;
1208 int msglen;
1209 char log_file[PATH_MAX];
1210 char *logrec;
1211 const char *committer;
1213 if (log_all_ref_updates < 0)
1214 log_all_ref_updates = !is_bare_repository();
1216 git_snpath(log_file, sizeof(log_file), "logs/%s", ref_name);
1218 if (log_all_ref_updates &&
1219 (!prefixcmp(ref_name, "refs/heads/") ||
1220 !prefixcmp(ref_name, "refs/remotes/") ||
1221 !strcmp(ref_name, "HEAD"))) {
1222 if (safe_create_leading_directories(log_file) < 0)
1223 return error("unable to create directory for %s",
1224 log_file);
1225 oflags |= O_CREAT;
1228 logfd = open(log_file, oflags, 0666);
1229 if (logfd < 0) {
1230 if (!(oflags & O_CREAT) && errno == ENOENT)
1231 return 0;
1233 if ((oflags & O_CREAT) && errno == EISDIR) {
1234 if (remove_empty_directories(log_file)) {
1235 return error("There are still logs under '%s'",
1236 log_file);
1238 logfd = open(log_file, oflags, 0666);
1241 if (logfd < 0)
1242 return error("Unable to append to %s: %s",
1243 log_file, strerror(errno));
1246 adjust_shared_perm(log_file);
1248 msglen = msg ? strlen(msg) : 0;
1249 committer = git_committer_info(0);
1250 maxlen = strlen(committer) + msglen + 100;
1251 logrec = xmalloc(maxlen);
1252 len = sprintf(logrec, "%s %s %s\n",
1253 sha1_to_hex(old_sha1),
1254 sha1_to_hex(new_sha1),
1255 committer);
1256 if (msglen)
1257 len += copy_msg(logrec + len - 1, msg) - 1;
1258 written = len <= maxlen ? write_in_full(logfd, logrec, len) : -1;
1259 free(logrec);
1260 if (close(logfd) != 0 || written != len)
1261 return error("Unable to append to %s", log_file);
1262 return 0;
1265 static int is_branch(const char *refname)
1267 return !strcmp(refname, "HEAD") || !prefixcmp(refname, "refs/heads/");
1270 int write_ref_sha1(struct ref_lock *lock,
1271 const unsigned char *sha1, const char *logmsg)
1273 static char term = '\n';
1274 struct object *o;
1276 if (!lock)
1277 return -1;
1278 if (!lock->force_write && !hashcmp(lock->old_sha1, sha1)) {
1279 unlock_ref(lock);
1280 return 0;
1282 o = parse_object(sha1);
1283 if (!o) {
1284 error("Trying to write ref %s with nonexistant object %s",
1285 lock->ref_name, sha1_to_hex(sha1));
1286 unlock_ref(lock);
1287 return -1;
1289 if (o->type != OBJ_COMMIT && is_branch(lock->ref_name)) {
1290 error("Trying to write non-commit object %s to branch %s",
1291 sha1_to_hex(sha1), lock->ref_name);
1292 unlock_ref(lock);
1293 return -1;
1295 if (write_in_full(lock->lock_fd, sha1_to_hex(sha1), 40) != 40 ||
1296 write_in_full(lock->lock_fd, &term, 1) != 1
1297 || close_ref(lock) < 0) {
1298 error("Couldn't write %s", lock->lk->filename);
1299 unlock_ref(lock);
1300 return -1;
1302 invalidate_cached_refs();
1303 if (log_ref_write(lock->ref_name, lock->old_sha1, sha1, logmsg) < 0 ||
1304 (strcmp(lock->ref_name, lock->orig_ref_name) &&
1305 log_ref_write(lock->orig_ref_name, lock->old_sha1, sha1, logmsg) < 0)) {
1306 unlock_ref(lock);
1307 return -1;
1309 if (strcmp(lock->orig_ref_name, "HEAD") != 0) {
1311 * Special hack: If a branch is updated directly and HEAD
1312 * points to it (may happen on the remote side of a push
1313 * for example) then logically the HEAD reflog should be
1314 * updated too.
1315 * A generic solution implies reverse symref information,
1316 * but finding all symrefs pointing to the given branch
1317 * would be rather costly for this rare event (the direct
1318 * update of a branch) to be worth it. So let's cheat and
1319 * check with HEAD only which should cover 99% of all usage
1320 * scenarios (even 100% of the default ones).
1322 unsigned char head_sha1[20];
1323 int head_flag;
1324 const char *head_ref;
1325 head_ref = resolve_ref("HEAD", head_sha1, 1, &head_flag);
1326 if (head_ref && (head_flag & REF_ISSYMREF) &&
1327 !strcmp(head_ref, lock->ref_name))
1328 log_ref_write("HEAD", lock->old_sha1, sha1, logmsg);
1330 if (commit_ref(lock)) {
1331 error("Couldn't set %s", lock->ref_name);
1332 unlock_ref(lock);
1333 return -1;
1335 unlock_ref(lock);
1336 return 0;
1339 int create_symref(const char *ref_target, const char *refs_heads_master,
1340 const char *logmsg)
1342 const char *lockpath;
1343 char ref[1000];
1344 int fd, len, written;
1345 char *git_HEAD = git_pathdup("%s", ref_target);
1346 unsigned char old_sha1[20], new_sha1[20];
1348 if (logmsg && read_ref(ref_target, old_sha1))
1349 hashclr(old_sha1);
1351 if (safe_create_leading_directories(git_HEAD) < 0)
1352 return error("unable to create directory for %s", git_HEAD);
1354 #ifndef NO_SYMLINK_HEAD
1355 if (prefer_symlink_refs) {
1356 unlink(git_HEAD);
1357 if (!symlink(refs_heads_master, git_HEAD))
1358 goto done;
1359 fprintf(stderr, "no symlink - falling back to symbolic ref\n");
1361 #endif
1363 len = snprintf(ref, sizeof(ref), "ref: %s\n", refs_heads_master);
1364 if (sizeof(ref) <= len) {
1365 error("refname too long: %s", refs_heads_master);
1366 goto error_free_return;
1368 lockpath = mkpath("%s.lock", git_HEAD);
1369 fd = open(lockpath, O_CREAT | O_EXCL | O_WRONLY, 0666);
1370 if (fd < 0) {
1371 error("Unable to open %s for writing", lockpath);
1372 goto error_free_return;
1374 written = write_in_full(fd, ref, len);
1375 if (close(fd) != 0 || written != len) {
1376 error("Unable to write to %s", lockpath);
1377 goto error_unlink_return;
1379 if (rename(lockpath, git_HEAD) < 0) {
1380 error("Unable to create %s", git_HEAD);
1381 goto error_unlink_return;
1383 if (adjust_shared_perm(git_HEAD)) {
1384 error("Unable to fix permissions on %s", lockpath);
1385 error_unlink_return:
1386 unlink_or_warn(lockpath);
1387 error_free_return:
1388 free(git_HEAD);
1389 return -1;
1392 #ifndef NO_SYMLINK_HEAD
1393 done:
1394 #endif
1395 if (logmsg && !read_ref(refs_heads_master, new_sha1))
1396 log_ref_write(ref_target, old_sha1, new_sha1, logmsg);
1398 free(git_HEAD);
1399 return 0;
1402 static char *ref_msg(const char *line, const char *endp)
1404 const char *ep;
1405 line += 82;
1406 ep = memchr(line, '\n', endp - line);
1407 if (!ep)
1408 ep = endp;
1409 return xmemdupz(line, ep - line);
1412 int read_ref_at(const char *ref, unsigned long at_time, int cnt, unsigned char *sha1, char **msg, unsigned long *cutoff_time, int *cutoff_tz, int *cutoff_cnt)
1414 const char *logfile, *logdata, *logend, *rec, *lastgt, *lastrec;
1415 char *tz_c;
1416 int logfd, tz, reccnt = 0;
1417 struct stat st;
1418 unsigned long date;
1419 unsigned char logged_sha1[20];
1420 void *log_mapped;
1421 size_t mapsz;
1423 logfile = git_path("logs/%s", ref);
1424 logfd = open(logfile, O_RDONLY, 0);
1425 if (logfd < 0)
1426 die("Unable to read log %s: %s", logfile, strerror(errno));
1427 fstat(logfd, &st);
1428 if (!st.st_size)
1429 die("Log %s is empty.", logfile);
1430 mapsz = xsize_t(st.st_size);
1431 log_mapped = xmmap(NULL, mapsz, PROT_READ, MAP_PRIVATE, logfd, 0);
1432 logdata = log_mapped;
1433 close(logfd);
1435 lastrec = NULL;
1436 rec = logend = logdata + st.st_size;
1437 while (logdata < rec) {
1438 reccnt++;
1439 if (logdata < rec && *(rec-1) == '\n')
1440 rec--;
1441 lastgt = NULL;
1442 while (logdata < rec && *(rec-1) != '\n') {
1443 rec--;
1444 if (*rec == '>')
1445 lastgt = rec;
1447 if (!lastgt)
1448 die("Log %s is corrupt.", logfile);
1449 date = strtoul(lastgt + 1, &tz_c, 10);
1450 if (date <= at_time || cnt == 0) {
1451 tz = strtoul(tz_c, NULL, 10);
1452 if (msg)
1453 *msg = ref_msg(rec, logend);
1454 if (cutoff_time)
1455 *cutoff_time = date;
1456 if (cutoff_tz)
1457 *cutoff_tz = tz;
1458 if (cutoff_cnt)
1459 *cutoff_cnt = reccnt - 1;
1460 if (lastrec) {
1461 if (get_sha1_hex(lastrec, logged_sha1))
1462 die("Log %s is corrupt.", logfile);
1463 if (get_sha1_hex(rec + 41, sha1))
1464 die("Log %s is corrupt.", logfile);
1465 if (hashcmp(logged_sha1, sha1)) {
1466 warning("Log %s has gap after %s.",
1467 logfile, show_date(date, tz, DATE_RFC2822));
1470 else if (date == at_time) {
1471 if (get_sha1_hex(rec + 41, sha1))
1472 die("Log %s is corrupt.", logfile);
1474 else {
1475 if (get_sha1_hex(rec + 41, logged_sha1))
1476 die("Log %s is corrupt.", logfile);
1477 if (hashcmp(logged_sha1, sha1)) {
1478 warning("Log %s unexpectedly ended on %s.",
1479 logfile, show_date(date, tz, DATE_RFC2822));
1482 munmap(log_mapped, mapsz);
1483 return 0;
1485 lastrec = rec;
1486 if (cnt > 0)
1487 cnt--;
1490 rec = logdata;
1491 while (rec < logend && *rec != '>' && *rec != '\n')
1492 rec++;
1493 if (rec == logend || *rec == '\n')
1494 die("Log %s is corrupt.", logfile);
1495 date = strtoul(rec + 1, &tz_c, 10);
1496 tz = strtoul(tz_c, NULL, 10);
1497 if (get_sha1_hex(logdata, sha1))
1498 die("Log %s is corrupt.", logfile);
1499 if (is_null_sha1(sha1)) {
1500 if (get_sha1_hex(logdata + 41, sha1))
1501 die("Log %s is corrupt.", logfile);
1503 if (msg)
1504 *msg = ref_msg(logdata, logend);
1505 munmap(log_mapped, mapsz);
1507 if (cutoff_time)
1508 *cutoff_time = date;
1509 if (cutoff_tz)
1510 *cutoff_tz = tz;
1511 if (cutoff_cnt)
1512 *cutoff_cnt = reccnt;
1513 return 1;
1516 int for_each_recent_reflog_ent(const char *ref, each_reflog_ent_fn fn, long ofs, void *cb_data)
1518 const char *logfile;
1519 FILE *logfp;
1520 char buf[1024];
1521 int ret = 0;
1523 logfile = git_path("logs/%s", ref);
1524 logfp = fopen(logfile, "r");
1525 if (!logfp)
1526 return -1;
1528 if (ofs) {
1529 struct stat statbuf;
1530 if (fstat(fileno(logfp), &statbuf) ||
1531 statbuf.st_size < ofs ||
1532 fseek(logfp, -ofs, SEEK_END) ||
1533 fgets(buf, sizeof(buf), logfp))
1534 return -1;
1537 while (fgets(buf, sizeof(buf), logfp)) {
1538 unsigned char osha1[20], nsha1[20];
1539 char *email_end, *message;
1540 unsigned long timestamp;
1541 int len, tz;
1543 /* old SP new SP name <email> SP time TAB msg LF */
1544 len = strlen(buf);
1545 if (len < 83 || buf[len-1] != '\n' ||
1546 get_sha1_hex(buf, osha1) || buf[40] != ' ' ||
1547 get_sha1_hex(buf + 41, nsha1) || buf[81] != ' ' ||
1548 !(email_end = strchr(buf + 82, '>')) ||
1549 email_end[1] != ' ' ||
1550 !(timestamp = strtoul(email_end + 2, &message, 10)) ||
1551 !message || message[0] != ' ' ||
1552 (message[1] != '+' && message[1] != '-') ||
1553 !isdigit(message[2]) || !isdigit(message[3]) ||
1554 !isdigit(message[4]) || !isdigit(message[5]))
1555 continue; /* corrupt? */
1556 email_end[1] = '\0';
1557 tz = strtol(message + 1, NULL, 10);
1558 if (message[6] != '\t')
1559 message += 6;
1560 else
1561 message += 7;
1562 ret = fn(osha1, nsha1, buf+82, timestamp, tz, message, cb_data);
1563 if (ret)
1564 break;
1566 fclose(logfp);
1567 return ret;
1570 int for_each_reflog_ent(const char *ref, each_reflog_ent_fn fn, void *cb_data)
1572 return for_each_recent_reflog_ent(ref, fn, 0, cb_data);
1575 static int do_for_each_reflog(const char *base, each_ref_fn fn, void *cb_data)
1577 DIR *dir = opendir(git_path("logs/%s", base));
1578 int retval = 0;
1580 if (dir) {
1581 struct dirent *de;
1582 int baselen = strlen(base);
1583 char *log = xmalloc(baselen + 257);
1585 memcpy(log, base, baselen);
1586 if (baselen && base[baselen-1] != '/')
1587 log[baselen++] = '/';
1589 while ((de = readdir(dir)) != NULL) {
1590 struct stat st;
1591 int namelen;
1593 if (de->d_name[0] == '.')
1594 continue;
1595 namelen = strlen(de->d_name);
1596 if (namelen > 255)
1597 continue;
1598 if (has_extension(de->d_name, ".lock"))
1599 continue;
1600 memcpy(log + baselen, de->d_name, namelen+1);
1601 if (stat(git_path("logs/%s", log), &st) < 0)
1602 continue;
1603 if (S_ISDIR(st.st_mode)) {
1604 retval = do_for_each_reflog(log, fn, cb_data);
1605 } else {
1606 unsigned char sha1[20];
1607 if (!resolve_ref(log, sha1, 0, NULL))
1608 retval = error("bad ref for %s", log);
1609 else
1610 retval = fn(log, sha1, 0, cb_data);
1612 if (retval)
1613 break;
1615 free(log);
1616 closedir(dir);
1618 else if (*base)
1619 return errno;
1620 return retval;
1623 int for_each_reflog(each_ref_fn fn, void *cb_data)
1625 return do_for_each_reflog("", fn, cb_data);
1628 int update_ref(const char *action, const char *refname,
1629 const unsigned char *sha1, const unsigned char *oldval,
1630 int flags, enum action_on_err onerr)
1632 static struct ref_lock *lock;
1633 lock = lock_any_ref_for_update(refname, oldval, flags);
1634 if (!lock) {
1635 const char *str = "Cannot lock the ref '%s'.";
1636 switch (onerr) {
1637 case MSG_ON_ERR: error(str, refname); break;
1638 case DIE_ON_ERR: die(str, refname); break;
1639 case QUIET_ON_ERR: break;
1641 return 1;
1643 if (write_ref_sha1(lock, sha1, action) < 0) {
1644 const char *str = "Cannot update the ref '%s'.";
1645 switch (onerr) {
1646 case MSG_ON_ERR: error(str, refname); break;
1647 case DIE_ON_ERR: die(str, refname); break;
1648 case QUIET_ON_ERR: break;
1650 return 1;
1652 return 0;
1655 struct ref *find_ref_by_name(const struct ref *list, const char *name)
1657 for ( ; list; list = list->next)
1658 if (!strcmp(list->name, name))
1659 return (struct ref *)list;
1660 return NULL;
1664 * generate a format suitable for scanf from a ref_rev_parse_rules
1665 * rule, that is replace the "%.*s" spec with a "%s" spec
1667 static void gen_scanf_fmt(char *scanf_fmt, const char *rule)
1669 char *spec;
1671 spec = strstr(rule, "%.*s");
1672 if (!spec || strstr(spec + 4, "%.*s"))
1673 die("invalid rule in ref_rev_parse_rules: %s", rule);
1675 /* copy all until spec */
1676 strncpy(scanf_fmt, rule, spec - rule);
1677 scanf_fmt[spec - rule] = '\0';
1678 /* copy new spec */
1679 strcat(scanf_fmt, "%s");
1680 /* copy remaining rule */
1681 strcat(scanf_fmt, spec + 4);
1683 return;
1686 char *shorten_unambiguous_ref(const char *ref, int strict)
1688 int i;
1689 static char **scanf_fmts;
1690 static int nr_rules;
1691 char *short_name;
1693 /* pre generate scanf formats from ref_rev_parse_rules[] */
1694 if (!nr_rules) {
1695 size_t total_len = 0;
1697 /* the rule list is NULL terminated, count them first */
1698 for (; ref_rev_parse_rules[nr_rules]; nr_rules++)
1699 /* no +1 because strlen("%s") < strlen("%.*s") */
1700 total_len += strlen(ref_rev_parse_rules[nr_rules]);
1702 scanf_fmts = xmalloc(nr_rules * sizeof(char *) + total_len);
1704 total_len = 0;
1705 for (i = 0; i < nr_rules; i++) {
1706 scanf_fmts[i] = (char *)&scanf_fmts[nr_rules]
1707 + total_len;
1708 gen_scanf_fmt(scanf_fmts[i], ref_rev_parse_rules[i]);
1709 total_len += strlen(ref_rev_parse_rules[i]);
1713 /* bail out if there are no rules */
1714 if (!nr_rules)
1715 return xstrdup(ref);
1717 /* buffer for scanf result, at most ref must fit */
1718 short_name = xstrdup(ref);
1720 /* skip first rule, it will always match */
1721 for (i = nr_rules - 1; i > 0 ; --i) {
1722 int j;
1723 int rules_to_fail = i;
1724 int short_name_len;
1726 if (1 != sscanf(ref, scanf_fmts[i], short_name))
1727 continue;
1729 short_name_len = strlen(short_name);
1732 * in strict mode, all (except the matched one) rules
1733 * must fail to resolve to a valid non-ambiguous ref
1735 if (strict)
1736 rules_to_fail = nr_rules;
1739 * check if the short name resolves to a valid ref,
1740 * but use only rules prior to the matched one
1742 for (j = 0; j < rules_to_fail; j++) {
1743 const char *rule = ref_rev_parse_rules[j];
1744 unsigned char short_objectname[20];
1745 char refname[PATH_MAX];
1747 /* skip matched rule */
1748 if (i == j)
1749 continue;
1752 * the short name is ambiguous, if it resolves
1753 * (with this previous rule) to a valid ref
1754 * read_ref() returns 0 on success
1756 mksnpath(refname, sizeof(refname),
1757 rule, short_name_len, short_name);
1758 if (!read_ref(refname, short_objectname))
1759 break;
1763 * short name is non-ambiguous if all previous rules
1764 * haven't resolved to a valid ref
1766 if (j == rules_to_fail)
1767 return short_name;
1770 free(short_name);
1771 return xstrdup(ref);